view libsanitizer/sanitizer_common/sanitizer_hash.h @ 145:1830386684a0

gcc-9.2.0
author anatofuz
date Thu, 13 Feb 2020 11:34:05 +0900
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//===-- sanitizer_common.h --------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements a simple hash function.
//===----------------------------------------------------------------------===//

#ifndef SANITIZER_HASH_H
#define SANITIZER_HASH_H

#include "sanitizer_internal_defs.h"

namespace __sanitizer {
class MurMur2HashBuilder {
  static const u32 m = 0x5bd1e995;
  static const u32 seed = 0x9747b28c;
  static const u32 r = 24;
  u32 h;

 public:
  explicit MurMur2HashBuilder(u32 init = 0) { h = seed ^ init; }
  void add(u32 k) {
    k *= m;
    k ^= k >> r;
    k *= m;
    h *= m;
    h ^= k;
  }
  u32 get() {
    u32 x = h;
    x ^= x >> 13;
    x *= m;
    x ^= x >> 15;
    return x;
  }
};
}  //namespace __sanitizer

#endif  // SANITIZER_HASH_H